1. Field of the Invention
The invention relates to a display device having a transistor. More specifically, the invention relates to a display device having an EL element and a thin film transistor (hereinafter referred to as a TFT) and the like formed on an insulator. Further, the invention relates to an electronic device having such a display device.
2. Description of the Related Art
In recent years, a display device having a light emitting element such as an electro luminescence (EL) element is actively developed. The light emitting element emits light by itself and does not use backlight which is required in a liquid crystal display (LCD) and the like, therefore, it is highly visible and suitable for fabricating in a thin form. Furthermore, its viewing angle is almost unlimited.
Generally, an EL element emits light when a current is supplied. Therefore, a different pixel configuration from LCD is suggested (refer to Non-patent Document 1).
[Non-Patent Document 1]
“Material technology and fabrication of elements regarding an organic EL display”, Technical Information Institute, January 2002, p. 179-195